Taste improving substances

ABSTRACT

The present invention in a first aspect relates to taste improvement of foodstuffs, beverages, tobacco products and oral care products, using a substance according to formula (I), edible salts or edible esters thereof: 
                         
It was found that substances represented by formula (I) are capable of modifying and complementing, the sensory impact of taste imparting substances. Thus, the present taste improving substances are advantageously applied in flavor compositions, foodstuffs, tobacco products and oral care products. Typical examples of taste improving substances according to the present invention include N-(2-hydroxyethyl) 3-hydroxypropionamide; N-(2-hydroxyethyl) 3-hydroxybutyramide; N-(2-hydroxyethyl) 4-hydroxybutyramide; N-(2-hydroxyethyl) N-5-hydroxypentanoylamide; N-(2-hydroxyethyl) 4-hydroxypentanoylamide; N-(2-hydroxyethyl) 3-hydroxypentanoylamide; N-(2-hydroxyethyl) 2-methyl-4-hydroxy-butyramide; N-(2-hydroxyethyl) 2-methyl-3-hydroxybutyramide; N-(2-hydroxyethyl) N-6-hydroxyhexanoylamide; N-(2-hydroxyethyl) 5-hydroxyhexanoylamide; N-(2-hydroxyethyl) 4-hydroxyhexanoylamide; N-(2-hydroxyethyl) 3-hydroxyhexanoylamide; N-(2-hydroxyethyl) 4-hydroxy-2-keto-3-methyl-pentanoylamide; N-(2-hydroxyethyl) 4-hydroxy-2-keto-3-methyl-hexanoylamide and mixtures thereof.

FIELD OF THE INVENTION

The present invention concerns taste improvement in foodstuffs,beverages, tobacco products and oral care products. More particularly,the present invention provides flavour compositions that can be used toconfer a fuller and richer taste to foodstuffs, beverages,pharmaceutics, tobacco products and oral care products. The flavourcompositions according to the invention are characterised by thepresence of one or more substances that are capable of modifying andcomplementing the impact of other flavour imparting substances.

The present invention also encompasses the use of the aforementionedtaste improving substances for improving the taste of foodstuffs,beverages, tobacco products and oral care products, as well as tofoodstuffs, beverages, tobacco products and oral care productscontaining these substances.

BACKGROUND OF THE INVENTION

The flavour of foodstuffs and beverages consists of two parts: the aromaand the taste. In general what is perceived through the olfactoryepithelium in the nasal cavity is referred to as ‘aroma’, whereas theterm ‘taste’ is generally used to describe the sensory impact that isperceived via the mouth, especially the tongue. The flavour sensationexperienced upon consumption, especially the taste, provides the finalanalysis of food prior to ingestion thereof. Visual and olfactory(smell) signals already give a first indication but only after intake ofthe food into the mouth the final decision is made either to ingest orto reject the food. Sweet taste is usually a signal that the food issafe (appetising) leading to ingestion of the food. The ‘reactions’ tosalt and umani are really dependent on the strength of the signal.Bitter and sour are usually experienced as repulsive taste sensationsthat can lead to rejection. Temperature is another measure by which thefood is judged just as well as aching sensations like capsaicin (hotpepper) and certain chemicals (like carbon dioxide).

In short, this means that taste is a very important and very complexsystem. Until recently most flavour research was focused towards aroma.Especially the last years a series of publications relating to moleculeswith a (positive) contribution to the taste of foodstuffs has emerged.

Such research has been stimulated significantly by the fact that quitesome receptors which are involved in the different taste sensations havebeen characterized by now (B. Lindemann; Nature 413, 219 (2001)).

Another interesting aspect of taste is that it can have an impact onaroma. It was reported that people having artificially sweetened waterin their mouth were significantly more sensitive to the smell ofbenzaldehyde than people having plain water in their mouth (P. Dalton etal, Nature Neurosci. 3, 431-432 (2000)).

Several screening systems have been described that make it possible toscreen, in a short time, large series of molecules for their(modulating) effect on taste response (cf. WO04055048, GB2396414,WO0177292 and US2004/0072254).

Most research on taste modulation so far has been devoted to tasteenhancement in savoury products. Several, mainly Japanese, publicationsdescribe umami molecules, i.e. alternatives to mono sodium glutamate(MSG) (H Suzuki et al, J Agric Food Chem 50, 313-318 (2002); K Shima etal, J Agric Food Chem 46, 1465-1468 (1998); Y Ueda et al, Biosc BiotechBiochem 61 1977 (1997)).

In EP 1291342, a ‘general taste enhancer’ is disclosed that was reportedto be suitable for enhancing sweetness as well.

In patent applications WO9704667 and WO04075663 tripeptides and aminoacid condensates with lactic acid and succinic acid are described thathave both their own taste as well as some enhancing properties. Alphaketo acids are reported to give body and mouthfeel to foodstuffs theyare added to (U.S. Pat. No. 6,287,620).

Chlorogenic acids are claimed to enhance sweetness and to reducebitterness (WO02100192).

Quite a bit of work has been devoted to find bitter taste suppressors(A. N. Pronin et al, Chemical Senses 29, 583-593 (2004); EP1401500; P.A. Breslin, Trends in Food Science & Technology 7, 390-399 (1996)).

In sweet and beverage products, further examples of the importance ofthe gustative dimension of flavourings have been reported. Theseexamples include taste attributes such as bitterness, tingling andcooling-freshness.

Bitterness is an essential aspect of some food flavours, among whichchocolate taste. Purine alkaloids, like theobromine and caffeine, aswell as amino acids and peptides have been known for a long time asbitter substances. In British patent no. GB 1420909 it is disclosed thatthe bitter flavour of cocoa can be reproduced using a combination of apurine alkaloid and an amino acid or an oligopeptide which ‘produces asurprisingly more natural simultaneously bitter and astringent flavournote than either of these types of substances alone’.

Menthol, an important constituent of peppermint oil, has a strong impacton flavoured products not only because of its mint smell but alsobecause it imparts a cooling and fresh taste. Next to mint flavouredproducts, it has been suggested to employ menthol in other types offlavour to impart a cool taste. US patent application no. US2005013846for example discloses how menthol and derivatives thereof can be used asflavouring in water continuous spreadable acidified food products toobtain table spreads exhibiting a fresh, cool taste impression.

Similarly, cinnamic aldehyde and eugenol, constituents of cinnamon oil,are used in flavouring composition for confectionery products, not onlyfor their smell but also because they impart a warm and tingling taste.The oral pungency of cinnamic aldehyde was described as burning andtingling by Cliff M and Heymann H [Journal of Sensory Studies 7(1992)279-290]. According to the same authors eugenol exhibits along-lasting numbing effect. Cinnamon oil has been proposed as a tasteimproving flavouring. International patent application no. WO9006689discloses that cinnamon oil, among other spice extracts, added to aminty flavour formulation, can be used to improve the long-lastingflavour of chewing-gum.

There is still a need for new so-called flavour modulating substancesthat provide a positive contribution to the flavour, especially taste,of foodstuffs, beverages, pharmaceutics, tobacco products and oral careproducts they are incorporated in. One objective of the presentinvention therefore is to provide such substances and compositionscomprising them.

SUMMARY OF THE INVENTION

The present inventors have surprisingly found that substancesrepresented by the following formula (I) can be used advantageously toimprove the taste of foodstuffs, beverages, tobacco products and oralcare products:

Therefore, the present invention relates to flavour compositions,foodstuffs, beverages, tobacco products and oral care products,comprising at least one substance according to formula (I).

Other aspects of the present invention relate to the use of saidsubstances for improving the taste of foodstuffs, beverages, tobaccoproducts and oral care products, and to a process for improving thetaste of these products.

The taste improving substances according to the present invention can beapplied advantageously to impart desirable taste attributes to theaforementioned products.

In addition, the present taste improving substances are capable ofmodifying the taste impact of other flavour ingredients contained withinthese same products, thereby improving the overall flavour quality ofthese products.

DETAILED DESCRIPTION OF THE INVENTION

Accordingly, the present invention in a first aspect relates to the usefor improving the taste of foodstuffs, beverages, tobacco or oral careproducts of a substance according to formula (I), or edible saltsthereof:

wherein:X represents C₁-C₃ alkyl, optionally substituted with one or moresubstituents selected from methyl and hydroxyl;and wherein Y represents linear C₂-C₅ alkylene or linear C₂-C₅alkenylene, each optionally substituted with one or more substituentsselected from the group of oxo, C₁-C₅ alkyl; and C₁-C₅ alkenyl, whichC₁-C₅ alkyl and C₁-C₅ alkenyl each may optionally be substituted withone or more hydroxyl groups.

The present inventors have found that the above-mentioned substances arevery useful flavour ingredients which, particularly in the presence ofother flavouring substances, are capable of imparting highly appreciatedtaste sensations to the products in which they are incorporated,specifically “cooling”, “pungent”, “sharp”, “hot” “tingling”, “bite”,“burning”, “warm”, “alcohol-like”, “continuity”, “complexity”,“expanding”, “salty”, “umami” and/or “long lasting”. Because of this,the present taste improving substances can be employed to improve thetaste (including “mouthfeel”) of foodstuffs, beverages, tobacco productsand oral care products.

The taste improving substances of the present invention as such arecapable of imparting highly desirable taste attributes. In addition, ithas been found that the taste improving substances according to theinvention are capable of complementing and modifying the sensory impactof other flavouring substances contained in the aforementioned products,including complementing and modulating “alcohol sensation”,“bitterness”, “hot taste sensation”, “cold taste sensation”,“carbonation effects”, “umami” and/or “salt taste impact”.

Throughout this document the terms “taste” and “flavour” are usedinterchangeably to describe the sensory impact that is perceived via themouth, especially the tongue, and the olfactory epithelium in the nasalcavity. The term “taste modifying” as used herein refers to thecapability of a composition or substance to alter the taste impact ofother, flavour imparting, substances present within the same product,with the proviso that this change in taste impact is not caused by theflavour contribution of said composition or substance per se, butinstead that it mainly results from the combined effect of on the onehand the taste improving composition or substance and on the other handthe other flavour imparting substances. The present substances combinethe capability of modifying the taste of other flavour substances with ataste contribution of their own. The favourable impact of the presenttaste improving substances is believed to be the result of thecombination of these two effects.

Because the taste improving substances according to the invention arenot particularly volatile, they do not produce a strong aroma impact,even though they can affect the aroma impact of other flavoursubstances. Here the term “aroma” refers to the aspect of taste that isperceived through the olfactory epithelium. Because of the lowvolatility of the present taste improving substances it is believed thatthe advantageous properties of these substances are somehow associatedwith the impact that these substances have on the sensory receptorslocated within the mouth.

It was found that particularly satisfying results can be obtained withtaste improving substances as defined herein before wherein X in formula(I) represents ethylene or propylene, optionally substituted with one ormore substituents selected from hydroxyl and methyl; more preferablyethylene, optionally substituted with one or more substituents selectedfrom hydroxyl and methyl. Most preferably X represents ethylene.

In a particularly preferred embodiment of the invention, Y in formula(I) represents linear C₂-C₅ alkylene or linear C₂-C₅ alkenylene, eachoptionally substituted with one or more substituents selected from thegroup of C₁-C₅ alkyl and C₁-C₅ alkenyl, each optionally be substitutedwith one or more hydroxyl groups. In a still more preferred embodimentof the invention, Y represents linear C₂-C₅ alkylene or linear C₂-C₅alkenylene, even more preferably C₃-C₅ alkylene or C₃-C₅ alkenylene,each optionally substituted with one or more substituents selected frommethyl, ethyl and propyl. Most preferably Y represents C₃-C₅ alkyleneoptionally substituted with one or more substituents selected frommethyl, ethyl and propyl.

In another particularly preferred embodiment of the invention, Y informula (I) represents linear C₂-C₅ alkylene substituted with an oxygenatom and optionally further substituted with one or more substituentsselected from of C₁-C₅ alkyl and C₁-C₅ alkenyl, each optionally besubstituted with one or more hydroxyl groups. Even more preferably, Yrepresents linear C₂-C₅ alkylene, still more preferably C₃-C₅ alkylene,substituted with an oxygen atom; which alkylene is optionally furthersubstituted with one or more substituents selected from methyl, ethyland propyl. Yet, in an even more preferred embodiment Y representslinear C₂-C₅ alkylene substituted with an oxygen atom and a methylgroup, said linear C₂-C₅ alkylene optionally being further substitutedwith one or more substituents selected from methyl, ethyl and propyl,most preferably from methyl and ethyl. Most preferably, the oxygen atomis attached to the carbon atom at the α-position relative to the amidemoiety such that Y represents an optionally substituted C₂-C₅α-ketoalkylene.

It will be clear to the skilled person that keto and enol forms of acarbonyl compound are tautomers existing in equilibrium with each other.Thus the aforementioned α-keto moiety will exist in equilibrium with thecorresponding α-enol moiety under normal circumstances, i.e. under thecircumstances that the present taste modulating substances will normallybe used.

Hence, suitable examples of taste modulating substances represented bythe aforementioned formula (I), that are particularly preferred for usein accordance with the invention include N-(2-hydroxyethyl)3-hydroxypropionamide; N-(2-hydroxyethyl) 3-hydroxybutyramide;N-(2-hydroxyethyl) 4-hydroxybutyramide; N-(2-hydroxyethyl)N-5-hydroxypentanoylamide; N-(2-hydroxyethyl) 4-hydroxypentanoylamide;N-(2-hydroxyethyl) 3-hydroxypentanoylamide; N-(2-hydroxyethyl)2-methyl-4-hydroxy-butyramide; N-(2-hydroxyethyl)2-methyl-3-hydroxybutyramide; N-(2-hydroxyethyl)N-6-hydroxyhexanoylamide; N-(2-hydroxyethyl) 5-hydroxyhexanoylamide;N-(2-hydroxyethyl) 4-hydroxyhexanoylamide; N-(2-hydroxyethyl)3-hydroxyhexanoylamide; N-(2-hydroxyethyl)4-hydroxy-2-keto-3-methyl-pentanoylamide; and N-(2-hydroxyethyl)4-hydroxy-2-keto-3-methyl-hexanoylamide.

As used herein the term ‘edible esters thereof’ encompasses any ediblederivative of the present flavour modulating substances and an acidformed by reaction of said acid with one of the hydroxyl groups presentin said flavour modulating substance. Typically said acid is an organicacid such as a substituted or non-substituted, linear or branched C₁-C₆carboxylic acid, more preferably a C₁-C₄ carboxylic acid, mostpreferably a C₁-C₃ carboxylic acid, or alternatively an inorganic acidsuch as phosphoric acid. Such esters will at least to a certain degree,possess some of the flavour characteristics of the correspondingsubstance according to formula (I) that is not esterified.

According to a preferred embodiment the present flavour modulatingsubstance is selected from the group of substances represented byformula (I) as defined herein before and salts thereof.

In another particularly preferred embodiment, the aforementionedcomposition is a flavour composition comprising, based on the total(dry) weight of the composition, at least 0.1 wt %, more preferably atleast 0.5 wt %, most preferably at least 1 wt %, of one or moreflavouring substances and at least 0.001 wt. %, preferably at least 0.01wt. %, of one or more of the present flavour modulating substances. Mostpreferably, the flavour composition contains at least 0.1 wt % of thepresent flavour modulating substances. Preferably the amount of thepresent flavour modulating substances does not exceed 80 wt %, morepreferably it does not exceed 40 wt %. As used herein, the term“flavouring substance”, refers to any substance that is not representedby formula (I) and that is capable of imparting a detectable flavourimpact, especially at a concentration below 0.1 wt. %, more preferablybelow 0.01 wt. %. Typically, the present flavouring substances belong toone or more of the chemical classes of alcohols, aldehydes, ketones,esters, ethers, acetates, nitriles, terpene hydrocarbons, nitrogenous orsulphurous heterocyclic compounds and essential oils, and saidflavouring substances can be of natural or synthetic origin. Many ofthese are listed in reference texts such as the book by S. Arctander(Perfume and Flavor Chemicals, 1969, Montclair, N.J., USA), or its morerecent versions, or in other works of a similar nature, as well as inthe abundant patent literature in the field of flavours.

Typically, in the present flavour composition, the one or more flavourmodulating substances and the one or more flavouring substances asdefined herein before are employed in a weight ratio within the range of10:1 to 1:100, preferably in a weight ratio of 5:1 to 1:50.

The flavour composition according to the present invention may suitablybe prepared in the form of a liquid, a paste or a powder. Flavourcompositions according to the present invention preferably comprise atleast one edible/food grade carrier, examples of which includemaltodextrin, modified starch, gum arabic, propylene glycol and ethanol.In a particularly preferred embodiment the flavour composition is a freeflowing powder.

Preferred examples of flavour compositions according to the presentinvention include sweet flavouring compositions, comprising one or moreof the present flavour modulating substances and at least one flavouringsubstance that is typically used in sweet flavour applications, moreparticularly in the field of dairy, beverage and/or confectionery, stillmore preferably a flavouring substance that is commonly used in thefield of flavouring alcoholic beverages, carbonated and still beverages.

In another preferred embodiment the present composition is a productselected from foodstuffs, beverages, tobacco products and oral careproducts, said product comprising at least 0.1 ppm, more preferably atleast 1 ppm, still more preferably at least 5 ppm, most preferably atleast 10 ppm of the present flavour modulating substances as definedherein before. Typically, the aforementioned products will contain theflavour modulating substances in a concentration of not more than 1000ppm, preferably of not more than 500 ppm, most preferably of not morethan 250 ppm. The present product will furthermore comprise one or moreflavouring substances as defined herein before and/or other flavourimparting substances.

Typical examples of said products include alcoholic beverages,carbonated beverages, still beverages, yoghurts, ice creams, desserts,confectioneries, sweet snacks, seasonings, sauces, stocks, soups anddressings. The benefits of the present invention may also be realised inoral care products such as toothpaste and mouthwash, and in tobaccoproducts, which includes any type of tobacco product for smoking as wellas for non-smoking applications. It is noted that tobacco-like productsare available for both smoking and non-smoking applications. The use ofthe present taste improving substances in these tobacco substitutes isalso encompassed by the present invention.

Preferably the present product is selected from the group of foodstuffs,beverages and tobacco products, even more preferably from the group offoodstuffs and beverages.

Preferably the present product is selected from the group of alcoholicbeverages, carbonated beverages, still beverages, yoghurts, ice creams,desserts, confectionery products, mouthwashes and toothpastes.

According to another particularly preferred embodiment the foodstuff orbeverage is an alcoholic foodstuff or an alcoholic beverage. As usedherein, the term ‘alcoholic foodstuff or alcoholic beverage’ refers tofoodstuffs or beverages comprising ethanol, preferably in an amount ofat least 0.5 wt %. More preferably said foodstuff or beverage comprisesless than 50 wt % of ethanol, still more preferably less than 40 wt % ofethanol, still more preferably it comprises 2-30 wt %, most preferably2-20 wt % of ethanol. Thus foodstuffs and beverages are provided by thepresent invention comprising at least 0.5 wt % of ethanol and at least0.01 ppm of a flavour modulating substance as defined herein before.

Another aspect the present invention relates to a process of improvingthe flavour of a product selected from foodstuffs, beverages, tobaccoproducts and oral care products, said process comprising incorporatinginto said product one or more flavour modulating substances as definedherein before, in an amount of at least 0.1 ppm, preferably of at least1 ppm, most preferably at least 5 ppm. Preferably said amount does notexceed 1000 ppm, more preferably it does not exceed 500 ppm, still morepreferably it does not exceed 250 ppm.

Still another aspect of the invention relates to the use of the flavourmodulating substances as defined herein before for improving the flavourof a product selected from foodstuffs, beverages, tobacco products andoral care products. A preferred embodiment relates to the use of thepresent flavour modulating substances, as defined herein before, formimicking and/or boosting ethanol sensation in foodstuffs or beverages,preferably, as mentioned herein before, in foodstuffs or beverages,comprising at least 0.5 wt % of ethanol. According to a preferredembodiment the present invention encompasses the use of the presentflavour modulating substances, as defined herein, in an amount ofbetween, 0.1-1000 ppm, more preferably 1-500 ppm.

Another embodiment of the invention relates to the use of the flavourmodulating substances as defined herein before for imparting and/ormodulating hot and/or cold taste sensation in the aforementionedproducts.

Yet another aspect of the present invention relates to processes ofpreparing flavour modulating substances, preferably flavour modulatingsubstances as defined herein before.

According to one embodiment, said process comprises reacting a lactonerepresented by the following formula (III) or a salt or ester thereofwith an amine represented by the following formula (IV) or a salt orester thereof:

wherein:X represents C₁-C₃ alkyl, optionally substituted with one or moresubstituents selected from methyl and hydroxyl; and wherein Y′represents linear C₂-C₅ alkylene or linear C₂-C₅ alkenylene, eachoptionally substituted with one or more substituents selected from thegroup of hydroxyl, provided that said hydroxyl group is a part of anenol moiety, C₁-C₅ alkyl; and C₁-C₅ alkenyl, which C₁-C₅ alkyl and C₁-C₅alkenyl each may optionally be substituted with one or more hydroxylgroups. Although, as mentioned herein before, enol and keto moieties aretautomers normally existing in equilibrium with each other, in thepresent lactones the enol-form will be energetically favoured over theketo-form.

Preferably the present reaction is performed by heating to reflux saidreactants in an organic solvent, such as toluene or pyridine, for aperiod of between 0.1-10 hours. According to a preferred embodiment, thereactants are used in a molar ratio of between 1:1-1:10. According tothe present processes the reaction products are typically obtained as aprecipitate and can be isolated by evaporating the solvent andoptionally further purified using any of the techniques known by theskilled person, such as chromatography and crystallization.

The invention is further illustrated by means of the following examples.

EXAMPLES Example 1

Stainless steel tubes, numbered 1-9, were filled with 15 g of ethanoland 2 g (=2 equivalents) of ethanolamine. To each tube 1 molarequivalent of one of the lactones as shown in table 1 was added. Thetubes were closed and the mixture was heated for 5 hours at 70° C. Aftercooling, the content of each tube was transferred to a round-bottomedflask and ethanol and excess ethanolamine were removed by heating undervacuum (3 mbar, 160° C.).

The products were analyzed by NMR. The samples were about 90-95% pureamide derivatives of the hydroxy-acid and ethanolamine, with someunreacted lactone and some ethyl esters of the correspondinghydroxy-acids.

TABLE 1 Tube: Lactone used Amount (g) 1 gamma-butyrolactone 1.4 2gamma-valerolactone 1.7 3 delta-valerolactone 1.7 4 gamma-caprolactone1.9 5 delta-caprolactone 1.9 6 delta-octalactone 2.3 7 delta-decalactone2.8 8 delta-undecalactone 3.0 9 delta-dodecalactone 3.3

Example 2

Two samples of fondant were prepared by mixing 65% Fondacreme (exBelgosuc NV Belgium) with 35% sugar syrup (67° Brix). 2500 Ppm mentholwas added as a 50% solution in propylene glycol. To a first sample(sample A), 50 ppm of N-(2-hydroxyethyl) 5-hydroxyhexanoyl amide (asprepared in example 1) was added. The second sample was the referencesample. The Samples were tasted by a professional panel.

Sample A gave more intense cooling than the reference sample. It isaggressive and its effect is immediate and through the whole oralcavity.

Example 3

Stainless steel tubes, numbered 10-20, were filled with 15 g of ethanoland 2 g (=2 equivalents) of ethanolamine. To each tube 1 molarequivalent of one of the lactones as shown in table 2 was added. Thetubes were closed and the mixture was heated for 5 hours at 70° C. Aftercooling, the content of each tube was transferred to a round-bottomedflask and ethanol and excess ethanolamine were removed by heating undervacuum (3 mbar, 160° C.).

50 ppm of each one of the reaction products obtained was added to adifferent sample containing a solution of 0.6% NaCl and 0.03% MSG thathad been prepared previously. These 11 samples and a reference solutionof 0.6% NaCl and 0.03% MSG, were tasted by a professional panel.

TABLE 2 Tube Starting material 10 delta-caprolactone 11 β propiolactone12 Ethyl 3-hydroxy-butyrate 13 γ butyrolactone 14 δ valerolactone 15 γvalerolactone 16 Ethyl3-hydroxy-valerate 17 Ethyl 6-hydroxy-caproate 18δ caprolactone 19 γ caprolactone 205-ethyl-3-hydroxy-4-methyl-2(5H)-furanone (EHMF)

All the Samples were judged to boost the (initial) salt impressioncompared with the reference solution.

Example 4

Two solutions of 0.6% NaCl and 0.03% MSG and 4 ppm pepper oleoresin (exWarner Jenkinson, St Louis, USA) were prepared.

To one sample (sample A), 50 ppm of N-(2-hydroxyethyl) 5-hydroxyhexanoylamide (as prepared in example 1) was added. The other sample was used asthe reference. Both samples were tasted by a professional panel.

In sample A the effect of initial hotness was increased and it gave morea hot, tingling after-taste, compared to the reference sample.

Example 5

Two solutions of 3% alcohol in water were prepared. To one sample(sample A), 50 ppm of N-(2-hydroxyethyl) 5-hydroxyhexanoyl amide (asprepared in example 1) was added. The other sample was used as thereference sample. Both samples were tasted by a professional panel.

Sample A had an alcohol-boosting effect and gave an aggressive alcoholimpression in the whole oral cavity compared to the reference sample.Sample A tasted like a 5-6% ethanol water mixture.

Example 6

Commercially available Odol mouthwater (GlaxoSmithKline) was obtainedfrom a local pharmacy and 4 solutions were prepared.

To a first sample (sample A), 50 ppm of N-(2-hydroxyethyl)5-hydroxyhexanoyl amide (as prepared in example 1) was added. Samples Awas tasted by a professional panel and compared with the mouthwaterwithout added N-(2-hydroxyethyl) 5-hydroxyhexanoyl amide.

Sample A had a stronger overall impact than the mouthwater without addedN-(2-hydroxyethyl) 5-hydroxyhexanoyl amide. It gave a more aggressivecooling in the whole oral cavity. Moreover sample A gave more initialcooling and more mouth-coating.

Example 7

Commercially available toothpaste was obtained from a local pharmacy and4 samples of paste were prepared.

To a first sample (sample A), 50 ppm of N-(2-hydroxyethyl)5-hydroxyhexanoyl amide (as prepared in example 1) was added andhomogenized. Samples A was tasted by a professional panel and comparedwith the toothpaste without added N-(2-hydroxyethyl) 5-hydroxyhexanoylamide.

Sample A had a stronger overall impact than the reference sample. Itgave a more aggressive cooling in the whole oral cavity. Moreover sampleA gave more initial cooling and more mouth-coating.

1. A flavour composition comprising at least 0.1 wt. % of flavouringsubstances and from about 0.001 to 50 wt. % of one or more tasteimproving substances according to formula (I), edible salts thereofand/or edible esters thereof:

wherein: X represents C₁-C₃ alkyl, optionally substituted with one ormore substituents selected from methyl or hydroxyl; and wherein Yrepresents a linear C₂-C₅ α-ketoalkylene optionally substituted with oneor more substituents selected from C₁-C₅ alkyl or C₁-C₅ alkenyl, eachoptionally substituted with one or more hydroxyl groups.
 2. The flavourcomposition according to claim 1, wherein Y represents a linear C₃-C₅α-ketoalkylene optionally substituted with one or more substituentsselected from methyl or ethyl.
 3. A product selected from the groupconsisting of foodstuffs, beverages, tobacco products and oral careproducts, comprising at least 0.1 ppm of a taste improving substanceaccording to formula (I) as defined in claim 1, or edible salts thereof.4. A process for improving the taste of a foodstuff, a beverage, atobacco product or an oral care product, comprising the step of addingto said foodstuff, beverage, tobacco product or oral care product ataste improving substance according to formula (I) as defined in claim1, or edible salts thereof, in an amount of at least 0.1 ppm.
 5. Theflavour composition according to claim 1, comprising from about 0.01 to10 wt. % of one or more taste improving substances according to formula(I), edible salts thereof and/or edible esters thereof.
 6. The flavourcomposition according to claim 1, wherein X represents ethylene orpropylene, optionally substituted with one or more substituents selectedfrom hydroxyl or methyl.
 7. The flavour composition according to claim2, wherein X represents ethylene or propylene, optionally substitutedwith one or more substituents selected from hydroxyl or methyl.